Author
Bjorneberg, David - Dave | |
SANTOS, F - UNIV. OF EVORA, PORTUGAL | |
CASTANHEIRA, N - UNIV. OF EVORA, PORTUGAL | |
MARTINS, O - UNIV. OF EVORA, PORTUGAL | |
REIS, J - UNIV. OF EVORA, PORTUGAL | |
AASE, J - USDA-ARS (RETIRED) | |
Sojka, Robert |
Submitted to: Journal of Soil and Water Conservation
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 3/12/2003 Publication Date: 12/1/2003 Citation: Bjorneberg, D.L., Santos, F.L., Castanheira, N.S., Martins, O.C., Reis, J.L., Aase, J.K., Sojka, R.E. 2003. Using polyacrylamide with sprinkler irrigation to improve infiltration. Journal of Soil And Water Conservation. 58(5):283-289. Interpretive Summary: Center pivot irrigation systems often apply water faster than it can soak into the soil. The same type of polyacrylamide (PAM) that controls furrow irrigation erosion can be applied through sprinkler irrigation to reduce runoff and soil erosion. Field studies were conducted near Kimberly, Idaho, USA and Monte dos Alhos near Alvalade do Sado, Portugal. Applying 1 to 3 lb/a of PAM (active ingredient) reduced runoff and soil erosion and improved infiltration compared to untreated plots. However, the additional water that infiltrated into the soil did not improve crop yield on the small plots in the USA. Technical Abstract: Center pivot irrigation systems often apply water at rates greater than the soil infiltration rate. Applying high molecular weight, water-soluble, anionic polyacrylamide (PAM) to the soil can improve infiltration and reduce soil erosion. The objective of this study was to determine if single and multiple PAM applications with sprinkler irrigation improve infiltration under field conditions. A two-year study conducted near Kimberly, Idaho, USA used a solid-set sprinkler system and a one-year study conducted in Monte dos Alhos near Alvalade do Sado, Portugal used a center pivot. At Kimberly, applying PAM with four irrigations (total applied PAM was 2.1 kg/ha in 2000 and 3.0 kg/ha in 2001) significantly reduced total measured runoff from 5.9 mm (2000) and 9.2 mm (2001) for the control to 2.0 and 2.1 mm. Total measured soil erosion was also reduced from 52 and 34 kg/ha for the control to 21 and 5 kg/ha for the multiple PAM treatment. Applying similar or greater amounts of PAM with a single irrigation reduced erosion compared to the control, but not runoff. In the Monte dos Alhos study, runoff was reduced by applying a total of 0.3 kg PAM/ha with a single irrigation (43 mm runoff) or three irrigations (65 mm runoff) compared to the control (111 mm runoff). Measured soil erosion was not significantly different among treatments. Applying PAM with multiple irrigations extended its effectiveness as long as the application rate was great enough to adequately stabilize the soil surface during the first irrigation. |